var liveBn;

function doClick(stem, bn, stick) {
  if (bn !== liveBn) {
    eval("document."+bn+".src='"+stem+bn+"_x.gif';");
    if (stick == true) {
      eval("document."+liveBn+".src='"+stem+liveBn+"_o.gif';");
      liveBn = bn;
    }
  }
}

function doOver(stem, bn) {
  if (bn !== liveBn) {
  eval("document."+bn+".src='"+stem+bn+"_v.gif';");
  }
}

function doDown(stem, bn) {
  if (bn !== liveBn) {
  eval("document."+bn+".src='"+stem+bn+"_x.gif';");
  }
}

function doUp(stem, bn) {
  if (bn !== liveBn) {
  eval("document."+bn+".src='"+stem+bn+"_v.gif';");
  }
}

function doOut(stem, bn) {
  if (bn !== liveBn) {
  eval("document."+bn+".src='"+stem+bn+"_o.gif';");
  }
}